P2P Collaborative Information Management

In the recent years, the evolution of a new wave of innovative network architectures labeled “peer-to-peer (p2p)” has been witnessed. Such architectures and systems are characterized by direct access between peer computers, rather than through a centralized server. File sharing is the dominant p2p application on the Internet, allowing users to easily contribute, search and obtain content. P2p file sharing architectures can be classified by their “degree of centralization”, i.e. to what extent they rely to one or more servers to facilitate the interaction between peers. Three categories are identified: Purely decentralized, partially centralized and hybrid decentralized.

Furthermore, highly dynamic p2p networks of peers with complex topology can be differentiated by the degree to which they contain some structure or are created adhoc. By structure we refer to the way in which the content of the network is located: Is there a way of directly knowing which peers contain some specific content. Three categories of systems are examined: Structured, loosely structured and unstructured.

Issues we are looking:

1) P2P Architectures.

2) Caching and Replication issue in P2P: We are designing a multi-user read/write peer-to-peer file system, which has no centralized or dedicated components, and it provides useful integrity properties without requiring users to fully trust either the underlying peer-to-peer storage system or the other users of the file system.

3) A fundamental paradigm in P2P is that of a large community of intermittently connected nodes that cooperate to share files. Because nodes are intermittently connected, the P2P community must replicate and replace as a function of their popularity to achieve satisfactory performance. Peers are intermittently connected, it is necessary to replicate popular content within the community to achieve satisfactory hit rates from within the community. Update strategy which is based on a hybrid push/pull rumor spreading algorithm takes into account these requirements. The goal of the update algorithm is to devise a fully decentralized, client and robust communication scheme which provides probabilistic guarantees rather than ensuring strict consistency.

4) Securing P2P data sharing applications is challenging due to their open and autonomous nature. Compared to a client-server system in which servers can be replied upon or trusted to always follow protocols, peers in a P2P system may provide no such guarantee. The environment in which a peer must function is a hostile one in which any peer is welcome to join the network; these peers cannot necessarily be trusted to route queries or responses correctly, store documents when asked to, or serve documents when requested.

Publications

2006 - Anirban Mondal, Sanjay Madria, Masaru Kitsuregawa, EcoRep: An Economic Model for efficient dynamic replication in Mobile-P2P networks , 13th International Conference on Management of Data (COMAD 2006), India

2006 - Anirban Mondal, Sanjay Madria, Masaru Kitsuregawa, CADRE: A Collaborative replica allocation and deallocation approach for Mobile-P2P networks, to appear in IEEE IDEAS'06

2006 - Anirban Mondal, Sanjay Kumar Madria, Masaru Kitsuregawa, CLEAR: An Efficient QoS-based dynamic replication scheme for Mobile-P2P Networks, accepted in DEXA'06 (23% acceptance rate)

2006 - Takahiro Hara and Sanjay K. Madria, Data Replication for Improving Data Accessibility in Ad Hoc Networks, to appear in IEEE Transaction on Mobile Computing

2005 - T. Hara and Sanjay Madria, Consistency Management among Replicas in Peer-to-Peer Mobile Ad Hoc Networks, accepted for IEEE SRDS 2005

2005 - Sanjay Madria and Sanjeev Agarwal, Adaptive Replication and Access Control of Multimedia Data in a P2P Environment, ito appear n proceedings of DEXA IEEE workshop 2005.

Researchers

Dr. Sanjay Madria

Dr. Bharat Bhargava, Purdue University

Dr. Takahiro Hara

Students

Abhinay Rathore